1. Field of the Invention.
The present invention relates in general to forced air central air conditioning systems, and more particularly, to forced air central air conditioning systems of the type having air control apparatus for regulating the flow of air to various rooms of the house or building being serviced by the system.
2. Description of the Prior Art.
In a forced air central air conditioning system, air is conditioned by a heating or cooling unit and forced through a plurality of ducts into the various living areas of the house or building being serviced by the system. The heating and cooling units are usually disposed in a closet in or adjacent to the house or building with some related equipment such as the heat exchanger being disposed outside of the house or building. The ducts typically extend from the heating and cooling units into an area outside of the living areas such as the attic or crawl space and then directly into the living areas at strategically selected locations. A thermostat automatically operates to turn the heating and cooling units on and off to maintain the air in the house or building at the desired temperature.
Unfortunately, most systems do not allow for separate control of the temperature in each living area. In houses or buildings having one or more living areas that are not in regular use, a great deal of energy is wasted. Although the flow of air to the living areas that are not regularly used can be regulated to some extent by opening and closing the air vents attached to the ends of the ducts, such practice is inconvenient and impractical. It is usually difficult and tedious to open and close all of the individual vents in the living areas not subject to regular use. Even when closed, most vents do not completely block the flow of air therethrough.
As a solution to the problem, various forced air central air conditioning systems and apparatus therefor that allow for separate temperature control of various living areas or zones of living areas have been developed. For example, U.S. Pat. No. 4,600,144 to Zelczer, issued July 15, 1986, discloses a zone control apparatus for forced air central heating and/or cooling systems that comprises a plurality of electrically or pneumatically operated flow control devices operatively associated with the air ducts of the system and a cycle controller for regulating the flow control devices to block or restrict the flow of air to the various rooms or zones of rooms with which the devices are associated. Although systems and apparatus of this type are a great improvement, they are not suitable for many systems. In residential houses or small buildings having only a small number of living areas that are not in regular use, the money spent to install complex electrically or pneumatically operated zone control equipment can be far greater than the money that the new equipment will save.
The present invention provides a relatively simple means for allowing separate temperature control of various living areas or zones of living areas of a house or building being serviced by a forced air central air conditioning system.